Assembly press



Feb. 23, 1954 G. R. EcKs-rElN 2,669,898

8 Sheets-Sheet l ATTORNEYS G. R. ECKSTEIN ASSEMBLY PRESS Feb. 23, 1954 8 Sheets-Shee'fI 2 Filed Dec. 14. 195C .x n. ....L l,... .v A

ATTORNEYS Feb. 23, 1954 Filed Deo. 14, 195C G. R. EC KSTEIN ASSEMBLY PRESS 8 Sheets-Sheet 3 A TTORNEYS ASSEMBLY PRESS Filed Deo. 14, 1950 8 Sheets-Sheet 4 IN VEN TOR. G50/9656. c/fs/T//v Feb. 23, 1954 Filed Dec. 14, 1950 8 Sheets-Sheet 5 r 35 32 g 60 6l I l 57 INVENTOR.

ATTORNEYS Feb. 23, 1954 Filed Dec. 14, 195C nga G. R. EcKs-rElN 2,669,898

ASSEMBLY PRESS 8 Sheets-SheeI 6 BVM HWT A TTOR/VEKS Feb. 23, 1954 G. R. EcKsTElN 2,669,898

ASSEMBLY PRESS Filed Deo. 14, 195C 8 SheetsSheet '7 VBY ATTORNEYS Feb. 23, 1954 G. R. EcKsTElN 2,669,898

ASSEMBLY PRESS Filed Dec. 14, 195C 8 Sheets-Sheet 8 Paga 5L Ola/'OFF VAL VE 610855 F 0 GE E ro 1/ /v E BLOW-OFF VALVE oPE/vs F V s q 54550 "D A C roP PUNCH L/Frs 701 PUNCH DES C E11/DS Cfr/nsf srnoks] FEED PAWL RET/7:1875

/IVSERT COMPONENT /N TOP DIE [TH/)w s mars) cR/MP/A/s mi` fri/fassa nmol/A Nc: S BLOW-UFF cLosfs TOP PIJ/VCH DESCENS VA L VE OPE /VS J (seca ,va s rea/rs) IN V EN TOR. G50/965A fC/fsf/A/ BY W 70,45 FuNc/f L/Frs M H ASSI/VELE' Patented Feb. 23, 1954 rUNITED ATENT OFFICE ASSEMBLY PRESS Application. December 14, 1950, Serial No. 201,278

9 Claims. l

This invention relates to an improved press and has particular reference to a press for assembling ammunition components or other small articles including several parts. The specic embodiment illustrated is arranged for assembling primers for small arms ammunition.

Operations of this character are usually carried out in multi-station dial or straight line transfer presses which are of relatively heavy and complicated c-onstruction with large i'ioor space requirements. Such presses have considerable inertia and may not be instantly stopped in the event of a malfunction or nnisfeed, which is dangerous when explosive components are being assembled. Further, no transfer machine ever developed could be certain to have perfect alignment at all4 operating stations under production working conditions.

`It is an object of my invention to provide' a small light Weight press capable of safely and o efficiently performing operations which would Fig. 7 is a view similar to Figs. 4, 5. and 6, with the mechanism in the position occupied at the bottom of the third Working stroke.

Fig. 8 is a partial horizontal sectional view on the line 8 8 of Figs. 3 and 4.

Fig. 9 is a cam diagram illustrating the sequence of the various operations.

GENERAL DESCRIPTION Referring to the drawings by characters of reference, it may be seen that I have provided a base I which supports a pair of pillars I I and a cross-bar I2, ythis, assembly comprising a main frame for the machine. Supported between the cross-bar I2 and the base I0 are a pair of columns I3 upon which there are guided for eolinear reciprocation a press gate I4 carrying a punch I5,

require the equivalent of a dial press having four A or more stations.

It is also an object of this invention to provide a variable stroke press in which several operations may be performed in each of several dif'- ferent but axially aligned locations. By axially aligning `the Working stations and the guides for the Working parts, perfect alignment in all working positions is readily achieved. v

A further object, closely connected with the general objective of safe operati-on, is the prol vision of a press in which the ultimate force exerted may be readily and accurately controlled.

The exact nature of the invention as well as other objects and advantages thereof will become moregapparent from considerati-on of the following specification referring to the attached drawings, in which:

Fig. 1 is a front perspective View of a machine rez'nbodying my invention.

Fig. 2 is arear perspective View of the same machine. l

' Fig. 3is a vertical sectional view taken through aplane indicated at 3-3 on Fig. 4.

' Fig. 4 'is a vertical sectional View taken in a plane at right angles to that illustrated in Fig. 3 and indicated thereon as fle-4l. The mechanism is at top dead center position.

Fig. 5 is a view similar to Fig. 4 with the mechanism shown in the position occupied at the bottom of the rst working stroke.

Fig. 6 is a view similar yto Figs. 4 and 5, with the .mechanism in the position' occupied at the bottom 'of the second working stroke.

an upper die plate I6, and a lower die plate I1. A symmetrical toggle assembly comprising a pair of oppositely broken toggle joints each including the substantially identical arms I8 joins the upper end of the frame to the gate I4 and is provided with thrust plates Ie at opposed knees of the toggle assembly. Mounted on one of the thrust plates is the double-acting pneumatic cylinder 20 provided with a piston rod 2l secured to the other thrust plate. Obviously, the operation of the air cylinder in one direction will draw the knees of the toggle closer to each other and thereby move the gate I4 downwardly While reverse operation of the air cylinder will have the eilect of raising the gate. During the reciprocation of the gate, the punch is brought into en'- gagement with the Work in the dies and the die plates are reciprocated into contact with each otherand with other too-ls to -be more specifically described later.

Supported across Ithe front of the machine is an endless feed belt 22 carried on suitable rollers 23 and 24. This belt is intermittently driven in one direction by a'gripper 25 associated with the .roller 23 and operated against a return spring 26 by an air cylinder 2l. A clutch 28 mounted on 'the frameprevents retrograde movement of the belt. Trays -29 are mounted in alignment with each run of the feed belt, permitting a com#- lponent to be fed from top tray 29 onto the top jrun lof the belt and carried thereby throughrtrack 30 into position to be fed to the die in the upper die plate. Similarly, components from bot-tom tray 29 may be pushed onto the lower run of the belt and 1carried thereby through track 3| into position to be fed to the lower die plate. The feed lingers 32 and 33 are both supported on a, block '3d-mounted for reciprocation and normally held suitable to the desired cyclic rate of the ma-VA chine, one revolution of the cam shaft producing one complete cycle of machine operation. i Each air cylinder is actuated in turn, as shown in the diagram of Fig. 9, to perform all .of the necessary operations in accurately timed sequence. Ob'v ously, the initial selection of the cross-sectional area of the pistons and the-.adjustment-of :the regulator determines the total force available for any given cylinder.

DETAILED .DESCRIPTION v Upperdie plate .The upper die *plate i6 -isrprovided A"wither-pair 'of guide-bushings yiii-s'lid'able von 'the columns` I3 rand with a pair of returnv springs' d5 actinglto hold theldie `lplate 'in anl uppermost "position The exact location-of this uppermost position Afis controlled bystopblocksilvsecured to the frame and cooperating with studs 4i' in thedie plate. A

.'disposedrbore ein fthe die -plateand is itself couniterboredxron`fthe. lower-,face `.to provide .a vdie refc'eiuing frecess. .-.The :upper fdief'lla lmountscin 'the meess--xandrtheidie and: die support block areboth secured to the die plateebyf a pair l.of fciamps'i.- 'Annaperture Elinor :rectangular cross-section ra- .diallywintersectsf the' i central bore 52 :ofv the: die Aand)provides1.sa:fteedivpassage .through y.-vvl'iicht-a Icomponentmay be lied 4from the-.upper run.- of :the :feed-belt 2.2..'.byttheiupper feed finger-3.2. -Ir-ithe `specific".example l'shownfe .the units' being. ,assembled:areffammunition:primersof the type. show-n inimyfcopending application,- Serial. No. 162,355, efiledt/Maytla A1950. A.The primer .retaining cups .may :beplaced conical end vup `on the. uppeixteed trayhs, 'from which they may -be manually Vrnrslifedronto .'the. upper run ot. .the lfeed beltaand (carried .single -le down the ,tr-ack Sil by. .the intere nuttentaadvanceaof. the feedbelt. Opposite ,the cleft rhand .edge -of .the aperture 5 l I.the feed track terminates against. a solid-stop Sila,- .andthe-feed .linger i 32 being .1 positione d. yin t opposition. tot-.the ,aperture ias it ...advancesT .strips .off the. iforemost component fromtheotrackand places. it inthe i-upperrdie in `ralignment :with .theaxial bore .there- V 1in. 'Atithe same time, .the advancing teed'inger block 34 carries a pair of stop blocks-53beneath the 1u-gs 154 Aon the., upper die plate. and. 031erl staaulo:'nary/ .ibarsq 55 `'associated with vthe iriain. frame. ;As,shownin xthe :sequence-diagram Fig.- 9., asv soon Las, the .feed .fing-er has. been advanced, .the press ,gated 4.and Vpunch ,4.5 are. moved` downwardly, t-he :,punchcenga'ging. the primer. retainer cup .and seatingt .inthe die. bore Y52. '..This action btakes .piacebecauselthe diefplate isheldagainstide- L .scending by fithe. Istop. y blocks. and I.the cup is ,not

pushed entirely .through .the die because .fthe puncholstopswhen the, press gate contactsthe .upper face. of ythe then stationary upperidie block.

-' Lower die plate "frhe'flower die'plate 'il'. Lis, like the upperiiiie fplate provided withsapair of. guide' bushings. `tiltdabl enifthencolumns vl-.3. '-Alsolilre the-upper iture leading=into the central bore 6l. stop-blocknGpabove referred to, is so dimensioned Y.asrtopositiontthe,aperture 60 in opposition to the i of return springs 45, always tending to raise the die plate to a position determined by stop blocks 56 which may be formed on the same members providing the stop blocks 4B.

'Ihe lower die plate is also provided with a centrally disposed aperture in alignment with that in the upper die plate and with the punch. .this aperture; against 'the-upper? face of the "lower die plate,'I havesprovidedra-edie support block 51 counterbored in its upper face to receive '1a-die 58. The die and die support block are retainedson the plate by a pair of clamps 59 bolted to the die plate.

'lheflowerdiariswprovided with a radial aper- The terminus of the track 3i along the upper surface of 4rthe'flower run of the feed belt 22 and in alignment with the lower feed iinger 33. When the feed ngerimoues :in: theiend. compon'ent-1in'ithe .fed finto. itlriee-centralJ bore in thel diesithe particular. component -iin-y this- .instance iaeiiigiithe :primer aand -a anvil f. assembly` entering iinto tithe 'primer disclosed 1in :my .aforeementioned roepending application.

Thea flower .die support/:block 5.1). is.- .also-.axially fboredf-.atfize and rinuthisrborereceives allprimer isupportlpunch 163 provided witha Al'iolcle1f.l54...and @tension-spring 65. .Thefspringds engaged fleetweerr agroove 5.6 on vthe i die y.suppoit-tabled:anda similar ,groove -S- .in .the y.punch holder.6.4,iac.tn'g ...always -to urge the .primensupport punch Itciiits -uppermost position v.in .-.the.-.diesupport,hlock :In 'the uppermost .position of-,thelower die-platethe .upper end of thefprimer,,supportrpunchds .main- -ftaineddiush -.-w.ith therlower vedgefpfl the aperture 60 by a punch positioning yokefsecnredtotthe base-plateof .thermachine and engaging the head 'of 7,the supporta-punch holder 64. f

During .the instand-second .working .strokes-of .the press gatethe primer supportpunchdsprevented from partaking in any downward'.move ment. of .the lower die block. bythe. ban 1EiLpositionedbetween .thefhead ofthe punch holdenand the machinefbase. l.'Ihisfbar, .691s reciprocable-.by .means whichwill be. discussed `in connectionwith ,thecrirnping die animan be.. positioned .toy 'allow thehead .of the holder. .toi descend. .to the baseb'f the machine.

As previously pointed out, i during .the first working stroke itheipressgate. and punch descend against. .thethen.fstationary upper..die plataa'nd pos'tiontheiprimer retainertherein. .Duringthe second working, Lstrioke .the upper.. die: plate isnot supported, ."the. .stop .blocks 54 -haying been withdrawn with '.the .feed Lfingers, .andJ the.. upperfjtlie moves linto.. contact .withilthe .upper face. of .the lower die and carries 'the lower"die .plate down with it. As the-lower die. plate. is; forced" down, the" hblder64 stops againstlthebarjSBAJandLthe primer ,in. .the lower ...die remains stationary.; on the end of the punch while the upper "die and the primer retainercupare pushed downover'it. When'the upper' die plate vreturns 'to'. its upper-ll most position, the `assembled but Auncrirnped primer .andr retainer 'remain 'in the -upper vdie nwhichzhas-avclosefit. 'on fthe' retainer lside walls.

Crimping die 35 plate by springsiiflg-rwhiieamant: cylnderfllzds carried on the slide and has a' piston rod which isfextensible in the direction of the block 'le to retractfthe slide when air pressure is applied thereto." The crimping die holder l5 is a bar of rectangular cross-section mounted on the slide 12in opposition'to the space between the faces of theupper and lower dies when both die plates vare'in the positions shown in Figs. 3 and 4.. Seated 'ina counterbore in the crimping die holder is ya crimping die i6 adapted to crimp or turn'in the edge 0f the primer retaining cup when the edge is forced into the die cavity. rlhis die isposltioned in the die holder to be coaxial with the-'upper and lower dies when the slide 'i2 is drawn toits innermost position by the springs i3. `A stein 1l extends downwardly from the block 12 and has a telescoping engagement with a tube 18 attached to the bar 69 previously referred to as` providing a support for the bottom or primer supportpunch 63. A hole T9 in the bar. til is positionedbeneath the punch when the bar is moved inwardly with the block 'l2 permitting the punch to be carried down with the lower die plate. Obviously, Athe descent of the press gate lil, when the crimping die is in operative position, will pick up the upper die plate and through the crimping die apply force to the lower die, carry ing it "downwardly until the stops 8i) contactv the machine base. At'this point further inotion of the crimping die is positively stopped and the full force of the air cylinder and toggle 1will be applied-to the purpose of crimping the assembly between :the end of the top punch i5 and the crimping die. Great force is available, for the toggle assembly may be designed to be nearly straight at this point and thus exert a considerably greater thrust than applied directly by the air cylinder.

ISUMMARY OF OPERATON l lower1 track 3|.

, After about degrees or. rotation or the cam shaft 42, the appropriate valve may be opened to disconnect air cylinder from pressure and per-- 4,mit-*lit to exhaust to atmosphere. As this cylin- ,deriexhausta the springs 3S draw in the block 34, carrying inthe feed fingers 32 and 33 as well asflthe vstop yblocks 53. The feed lingers each vcarry a component from the feed track through .theradial opening in the appropriate die and position it therein in alignment with the axial die bore.'A

`Shortly vafter the components are fed into the dies,.pressure is applied to the iront side of the piston on the cylinder 2t and the back end of thegc'ylinder is permitted to exhaust to atmosphere," thus lowering the press gate in its first stroke. the punch descends, the upper olie plate is supported bythe stop blocks 53 and the punch carries the primer retainer from a position in alignment with the radial passage in the die down into the axial bore. As the retainer enters the axial bore, it pushes ahead of it the primer assembled and crimped in the precedingl cycle'. Theejected unit falls into a chute 8i carried by thefeed finger block 34 into the space l-eneath ,the upper'die.

" Sometime'after the advance ol' the iced lingers,

5 the pressure may be released from. the belt Afeed cylinder 2l, permitting the spring 26 to return the gripper 25 to its neutral position. `The drag of the gripper 25 over the .belt does not produce a retrograde movement of the belt because ofthe holding action of the clutch 28. Conveniently, this retraction of the belt feed pawl may take place during the first working stroke of the punch. f x

It may be noted that the rst working stroke is relatively short and that during this stroke the toggle assembly is so extended as to have a relatively poor mechanical advantage. This condition is tolerable and, in fact, desirable, since relatively little force lis normally required to eject the previously completed assembly and insert the new retainer. In the event of a machine jam of any kind, suiiicient force is not available to crush and possibly explode the assembled primer. It will be obvious that the air cylinder is not constrained to complete any given length of stroke but simply applies a resilient force tending to move the gate until the air is cut'oi. This is in marked contrast to a crank or other mechanical press which must complete a fixed stroke and which usually has enough inertia to converta jam into a tool smash-up.

After an allowance of about thirty degrees of camshaft rotation for `the rst working stroke, air is applied to the back end otthevcylinder 20 while the front end exhausts, thus raising the press gate. Simultaneously, or slightly before the lifting of the top punch, air is applied to the cylinder 35 to retract the feed linger assembly. Preferably, considerable pressure should be available in the cylinder l35 at the time the press gate actually lifts to result in a snap retraction of the feed lingers and the delivery chute when the stop blocks are released. Such a snap retraction is desirable, because the impulse imparted to the ejected primer just previously deposited in the delivery chute is sufficient to insure that primers will not pile up in the end of the chute.

The press gate having returned to top dead center and the feed finger assembly returned t0 its outer position, the next operation is the sec-'- ond working stroke of the press. During this second working stroke, the press gate and punch descend, picking up the top die plate and backing up the retainer therein with the end of the holf low punch. The top die then contacts the upper face of the lower die, carrying the lower die downward while the primer support punch car-,- ried by the lower die is able to move only a short distance before it is stopped by impingement upon the bar S9. Thereaftenthe lower die is forced down over the primer support punch and the primer which has been atrest upon theend of the punch is forced into the retainer heldfin the upper die. Downward 'movement of lthe units of the press ceases when'the toggle reaches its completely collapsed position, the end position of the primer being determined by the adjustment of the primer support punch inthe holder 65. Upon the reversal of the valve connections to the cylinder 20, the press gate returns to its uppermost position, the two die plates being returned by the springs 45 to their normal positions. v

The completion of a good crimp is, to a considerable extent, dependent upon having a clean crimping die and shortly before the crimping die is moved into active position, air is released through tube 82 to blow off any 4fragmentsjof metal or other material which may have'lodged scribed in claim 7 of spring means acting to engage said temporary die plate stopping means with the die plate; a fluid pressure cylinder associated with said plate stopping means and provided with a piston arranged to disengage said die plate stopping means against the urgingy of said spring; reversible valve means to connect said cylinder to a supply of fluid pressure; and additional cam means on said shaft arranged to control said reversible valve means to engage and disengage said stopping means in predetermined sequential relation to the extension and retraction of said toggle joint.

9. In a press, the combination with that described in claim 8 of die means mounted for lateral movement into alignment with said punch and with said work-holding dies; spring means urging said die means to move into said alignment; fluid pressure cylinder means associated with said die means and provided with a. piston arranged to retract said die means against the urging of the spring; valve means arranged to interchangeably connect said cylinder to exhaust or to a source of iluid pressure; and additional cam means on said cam shaft arranged to actuate said valve means to shift said die means in predetermined timed sequence to the operation of said toggle joint.

GEORGE R. ECKSTEIN.

References Cited in the file of this patent UNITED STATES PATENTS 

